NextArena Tournament Tools

co.nextarena/tournament-toolsnextarena.costreamable-httpv0.1.2Scanned 1 hour ago

Free padel Americano and Mexicano draws, pickleball round robins and knockout brackets.

6 tools: 5 change things and 1 only read.

Reads private data · 0
Reads text others write · 0
Can send data out · 0
4 findings

Anlyon alternative

5 of these tools change something. Run those as governed actions.

Declare what an action changes, and Anlyon puts it under a shared limit, binds every approval to the exact request, and grades the outcome. It works on any HTTPS API you can describe as an action.

Anlyon does not run, proxy or govern this MCP server. A tool your own code calls directly is not routed through Anlyon and is not governed by it.

Import an OpenAPI spec →

Tools

Grouped by what each tool does, most consequential first. Open one for its reasons and full description; descriptions are the publisher's own words.

6 tools

Changes things 5Creates or changes something that can be changed back.Claude Code: ask

calculate_mexicano_standingsMANDATORY BEFORE CALLING: the user must have chosen BOTH sport and format for THIS tournament.No findings
Why it is in this group
- Nothing in its name or description says what it does, so it is counted as a write.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
Description, as the server wrote it
MANDATORY BEFORE CALLING: the user must have chosen BOTH sport and format for THIS tournament. If either is missing, ask instead of generating, or call get_supported_tournament_options to discover choices. Never infer sport or format from unrelated previous conversations, previous tool use, player/court counts or a default. 'Make a tournament for 20 players on four courts' requires clarification, not an Americano. Reuse choices explicitly confirmed earlier in this same tournament setup. Clarify individuals versus fixed teams when ambiguous. Use this when the user wants individual PADEL Mexicano standings from completed round scores, without generating another round. Supply config and all completed previousRounds. Each player receives their pair's rally points. Does not save or publish results.
Annotations the server declares
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: false
generate_americanoMANDATORY BEFORE CALLING: the user must have chosen BOTH sport and format for THIS tournament.1 finding
Why it is in this group
- The name "generate_americano" says "generate": a word for a change.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
Findings
- Warn
  The server marks "generate_americano" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
  Matched text
  annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":false}; The name "generate_americano" says "generate": a word for a change.
  What this check looks for
Description, as the server wrote it
MANDATORY BEFORE CALLING: the user must have chosen BOTH sport and format for THIS tournament. If either is missing, ask instead of generating, or call get_supported_tournament_options to discover choices. Never infer sport or format from unrelated previous conversations, previous tool use, player/court counts or a default. 'Make a tournament for 20 players on four courts' requires clarification, not an Americano. Reuse choices explicitly confirmed earlier in this same tournament setup. Clarify individuals versus fixed teams when ambiguous. Use this when the user wants a PADEL Americano tournament (not pickleball; use generate_round_robin with rotating_doubles for pickleball rotating partners), rotating doubles partners, balanced rests and varied opponents. Plans rounds before play. Each entrant is an individual player. Always show the returned schedule in full, round by round: start time, court, both pairs and who rests. Never replace it with a summary. Set restMinutes when the user wants a break between rounds. After the schedule, pass on any warning about uneven rests and its suggested round counts. Does not save or publish an event; do not use for score-led Mexicano pairings.
Annotations the server declares
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: false
generate_bracketMANDATORY BEFORE CALLING: the user must have chosen BOTH sport and format for THIS tournament.1 finding
Why it is in this group
- The name "generate_bracket" says "generate": a word for a change.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
Findings
- Warn
  The server marks "generate_bracket" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
  Matched text
  annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":false}; The name "generate_bracket" says "generate": a word for a change.
  What this check looks for
Description, as the server wrote it
MANDATORY BEFORE CALLING: the user must have chosen BOTH sport and format for THIS tournament. If either is missing, ask instead of generating, or call get_supported_tournament_options to discover choices. Never infer sport or format from unrelated previous conversations, previous tool use, player/court counts or a default. 'Make a tournament for 20 players on four courts' requires clarification, not an Americano. Reuse choices explicitly confirmed earlier in this same tournament setup. Clarify individuals versus fixed teams when ambiguous. Use this when the user wants a PICKLEBALL seeded or random single-elimination tournament bracket with byes, court assignments and provisional match times. Always show every returned match with its round, court and time; never replace it with a summary. Does not record winners, save an event or support double elimination.
Annotations the server declares
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: false
generate_mexicano_roundMANDATORY BEFORE CALLING: the user must have chosen BOTH sport and format for THIS tournament.1 finding
Why it is in this group
- The name "generate_mexicano_round" says "generate": a word for a change.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
Findings
- Warn
  The server marks "generate_mexicano_round" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
  Matched text
  annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":false}; The name "generate_mexicano_round" says "generate": a word for a change.
  What this check looks for
Description, as the server wrote it
MANDATORY BEFORE CALLING: the user must have chosen BOTH sport and format for THIS tournament. If either is missing, ask instead of generating, or call get_supported_tournament_options to discover choices. Never infer sport or format from unrelated previous conversations, previous tool use, player/court counts or a default. 'Make a tournament for 20 players on four courts' requires clarification, not an Americano. Reuse choices explicitly confirmed earlier in this same tournament setup. Clarify individuals versus fixed teams when ambiguous. Use this when the user asks to generate or run a PADEL Mexicano tournament. Creates round 1 from player count and courts, or the next round using all completed prior scores and individual standings. Always show the returned round in full: time, court, both pairs and who rests. Future pairings cannot be known in advance. If players must rest (count not a multiple of 4, or more players than court places), offer config.ranking: average (points per match) so extra rests do not cost anyone, and suggest a round count that gives equal rests. Set config.restMinutes when the user wants a break between rounds. Stateless: return the prior state with scores filled in. Does not save, publish or change a live tournament.
Annotations the server declares
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: false
generate_round_robinMANDATORY BEFORE CALLING: the user must have chosen BOTH sport and format for THIS tournament.1 finding
Why it is in this group
- The name "generate_round_robin" says "generate": a word for a change.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
Findings
- Warn
  The server marks "generate_round_robin" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
  Matched text
  annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":false}; The name "generate_round_robin" says "generate": a word for a change.
  What this check looks for
Description, as the server wrote it
MANDATORY BEFORE CALLING: the user must have chosen BOTH sport and format for THIS tournament. If either is missing, ask instead of generating, or call get_supported_tournament_options to discover choices. Never infer sport or format from unrelated previous conversations, previous tool use, player/court counts or a default. 'Make a tournament for 20 players on four courts' requires clarification, not an Americano. Reuse choices explicitly confirmed earlier in this same tournament setup. Clarify individuals versus fixed teams when ambiguous. For PICKLEBALL only: generate singles, fixed-team or rotating-doubles round-robin fixtures. Establish sport first; offer pickleball round robin or knockout, and padel Americano or Mexicano. Before calling, establish singles vs fixed teams vs rotating partners, whether the count means players or teams, full round robin vs a limited number of rounds, match duration and available session time. Never infer fixed teams from an individual player count. A full singles/fixed-team draw has n*(n-1)/2 matches and may require multiple court waves per round. Pickleball rotating partners use mode rotating_doubles here, with a numeric round count, not generate_americano. Do not promise everyone meets everyone in rotating doubles. Always show the returned fixtures in full, round by round; never replace them with a summary. Return total matches and estimated session length; if it exceeds the user's time, discuss a shorter partial draw rather than silently changing format. Free draft only; no saving or publishing.
Annotations the server declares
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: false

Only reads 1Looks things up and changes nothing.Show 1 read-only tool

get_supported_tournament_optionsUse for a generic tournament request with no confirmed sport or format, or to discover NextArena's supported sports, formats, entrant types and limits.No findings
Why it is in this group
- The name "get_supported_tournament_options" says "get": a word for reading.
Description, as the server wrote it
Use for a generic tournament request with no confirmed sport or format, or to discover NextArena's supported sports, formats, entrant types and limits. Does not generate a tournament or select defaults. With no sport, ask Pickleball or padel first; with a confirmed sport, return only its formats. Do not display all formats as interchangeable across sports.
Annotations the server declares
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: false

This is not a safety rating, and no finding is not a safety guarantee. The groups and findings come from fixed checks of the tool definitions the server returned on the date shown, not from its code or what it does when called. How the checks work.

Exfil surface

Which tools read private data, which read text someone else can write, and which can send data out. One of each is a path a prompt injection can use.

No private-data, untrusted-input, outbound path in this server alone: no tool is tagged private-data or untrusted-input or outbound.

Reads private data0: Reads files, mail, messages, databases, secrets, calendars or repositories.
Reads text others write0: Brings in text someone else can write: web pages, inbound email, messages, issues and comments.
Can send data out0: Can carry data to people or systems: it sends, posts or publishes, or takes a recipient, channel or URL.

Other servers in the same agent add their own tools to these paths. Audit your whole setup to see them together.

Findings

Matches of fixed checks, with the text they matched.

4 warn

Warngenerate_round_robin
The server marks "generate_round_robin" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
Matched text
annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":false}; The name "generate_round_robin" says "generate": a word for a change.
What this check looks for
Warngenerate_americano
The server marks "generate_americano" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
Matched text
annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":false}; The name "generate_americano" says "generate": a word for a change.
What this check looks for
Warngenerate_bracket
The server marks "generate_bracket" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
Matched text
annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":false}; The name "generate_bracket" says "generate": a word for a change.
What this check looks for
Warngenerate_mexicano_round
The server marks "generate_mexicano_round" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
Matched text
annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":false}; The name "generate_mexicano_round" says "generate": a word for a change.
What this check looks for

History

Changes to its tool definitions and to its remote endpoint, newest first.

No change seen yet. Its tools are rescanned every day, and a remote endpoint is looked at once a week.

All changes to this server

Install

Pinned to version 0.1.2. Values in angle brackets are yours to fill in.

claude mcp add --transport http tournament-tools https://www.nextarena.co/api/mcp

claude mcp add --transport http tournament-tools https://www.nextarena.co/api/mcp

Run in a terminal.

Claude Code permissions

Allow the reads, ask before a change or a way out, deny the deletes. Paste into .claude/settings.json.

.claude/settings.json

{
  "permissions": {
    "allow": [
      "mcp__tournament-tools__get_supported_tournament_options"
    ],
    "ask": [
      "mcp__tournament-tools__generate_round_robin",
      "mcp__tournament-tools__generate_americano",
      "mcp__tournament-tools__generate_bracket",
      "mcp__tournament-tools__generate_mexicano_round",
      "mcp__tournament-tools__calculate_mexicano_standings"
    ],
    "deny": []
  }
}

Tools that only read are allowed, tools that change things ask first, tools that delete or cancel are denied. A read that can send data out (it takes a URL, say) asks first too. It assumes the server is installed as tournament-tools. Review it before you use it.

Keep the decision: fail CI when the tools change, follow every change, or show a badge.

Pin in CI

Fail a build when the tools you reviewed are not the tools the server serves today.

curl -s "https://anlyon.dev/api/v1/servers/co.nextarena/tournament-tools/verify?hash=73737ff636dc750c7854d142be9140df217215c0f7c024deb388ec2b6fac53ee" | jq -e '.changed == false'

Pinned hash 73737ff636dc, from Oct 25, 2026, 22:17 UTC.

Watch

Get told when its tools change: a new tool, a new description, a new class.

https://anlyon.dev/servers/co.nextarena/tournament-tools/changes.xml

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Badge

[![anlyon.dev](https://anlyon.dev/badge/co.nextarena/tournament-tools.svg)](https://anlyon.dev/servers/co.nextarena/tournament-tools)

Source: MCP Registry. Synced Oct 25, 2026, 22:17 UTC.